If you want to try backup your AIX clients on Network Installiation Manager(NIM),you must edit niminfo file on your NIM Client.
export NIM_NAME=clientname
export NIM_HOSTNAME=clientname
export NIM_CONFIGURATION=standalone
export NIM_MASTER_HOSTNAME=nimservername
export NIM_MASTER_PORT=1058
export NIM_REGISTRATION_PORT=1059
export NIM_SHELL="shell"
export NIM_MASTERID=**************
export REMAIN_NIM_CLIENT=no
export NIM_LICENSE_ACCEPT=yes
export RC_CONFIG=rc.bos_inst
export NFS_RESERVED_PORT=yes
export NIM_BOS_FORMAT=mksysb
export NIM_HOSTS=" 127.0.0.1:loopback:localhost clientip:clientname nimserverip:nimservername "
export NIM_BOSINST_ENV="/../SPOT/usr/lpp/bos.sysmgt/nim/methods/c_bosinst_env"
export NIM_BOSINST_RECOVER="/../SPOT/usr/lpp/bos.sysmgt/nim/methods/c_bosinst_env -a hostname=clientname"
export NIM_BOSINST_DATA=/NIM_BOSINST_DATA
export NIM_BOS_IMAGE=/NIM_BOS_IMAGE
